Ditching the last flight of a round trip with a twist
 

I will be flying LAS - LHR - DUB (in November), arriving at LHR at 1500 and scheduled to depart at 1820, and arrive in DUB at 1940. I'd like to ditch the LHR - DUB leg and instead book LHR - OTP (1745 - 2300) on the same day. While I have ditched the last leg of a flight before on BA, I have never wanted an overlapping booking like this. Is this possible while booking in advance? Would it be polite to un-check-in myself from the LHR - DUB flight? If so, at what point should I do so?

No issue booking whatever you want is overlapping. Yes it would be polite to uncheck yourself and as you know you’ll need to be hbo.

Thank you!

I really think that airlines frown upon passengers ditching flights - even if insured, getting the aeroplane replaced or repaired takes time

Wouldn't they see that you have a double booking and cancel the newest one? UA did that to me (in my case, I just forgot to cancel the first one...had intended to).

BA will not do this for any other booking, only if it‘s clearly a duplicate booking on the same flight(s). I don‘t think UA do either, only if at least one sector is on the same flight.

even a duplicate booking on the same flight doesn't seem to provoke BA to pro-actively cancel one. in that instance the main issue is you need to cancel one before olci opens.

for overlapping bookings on separate flights i haven't heard of any issues before with BA cancelling one, so it shouldn't be an issue at all.

That’s nice of BA. UA absolutely will cancel an “impossible” booking (where you couldn’t fly the first trip and the second trip).